To cite package ‘logistf’ in publications use:

Heinze G, Ploner M, Jiricka L, Steiner G (2025). logistf: Firth's Bias-Reduced Logistic Regression. R package version 1.26.1, https://github.com/georgheinze/logistf.

Corresponding BibTeX entry:

  @Manual{,
    title = {logistf: Firth's Bias-Reduced Logistic Regression},
    author = {Georg Heinze and Meinhard Ploner and Lena Jiricka and
      Gregor Steiner},
    year = {2025},
    note = {R package version 1.26.1},
    url = {https://github.com/georgheinze/logistf},
  }